* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Arial', 'Microsoft YaHei', sans-serif;
    background: #f5f5f5;
    min-height: 100vh;
}

.container {
    width: 100%;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* 导航栏 */
.navbar {
    width: 100%;
    height: 50px;
    background-color: white;
    display: flex;
    align-items: center;
    padding: 0 30px;
}

.navbar a {
    display: inline-block;
    width: 80px;
    color: black;
    font-size: 15px;
    line-height: 50px;
    text-decoration: none;
    text-align: center;
    transition: background-color 0.3s;
}

.navbar a:hover {
    background-color: green;
}

.navbar .logout {
    float: right;
}

.navbar .login {
    float: right;
}

/* 题目列表区域 */
.question_list {
    width: 100%;
    max-width: 900px;
    margin: 50px auto;
    padding: 0 20px;
    text-align: center;
}

.question_list h1 {
    color: green;
    font-size: 32px;
    margin-bottom: 40px;
    font-weight: 500;
}

.question_list table {
    width: 100%;
    border-collapse: collapse;
    background-color: rgb(243, 248, 246);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    border-radius: 8px;
    overflow: hidden;
}

.question_list table thead {
    background-color: #e8f5e9;
}

.question_list table th {
    padding: 15px 12px;
    text-align: center;
    color: #2e7d32;
    font-weight: 500;
    font-size: 16px;
}

.question_list table .item {
    height: 50px;
    font-size: 15px;
    font-family: 'Lucida Sans', 'Lucida Sans Regular', 'Lucida Grande', 'Lucida Sans Unicode', Geneva, Verdana, sans-serif;
}

.question_list table tbody tr {
    border-bottom: 1px solid #e0e0e0;
    transition: background-color 0.2s;
}

.question_list table tbody tr:hover {
    background-color: #f1f8f4;
}

.question_list table tbody tr:last-child {
    border-bottom: none;
}

.question_list table td {
    padding: 15px 12px;
    text-align: center;
}

.question_list table .item a {
    text-decoration: none;
    color: black;
    font-weight: 500;
    transition: color 0.3s;
}

.question_list table .item a:hover {
    color: green;
    text-decoration: underline;
}

/* 页脚 */
.footer {
    width: 100%;
    height: 50px;
    text-align: center;
    line-height: 50px;
    color: #999;
    margin-top: auto;
    padding: 20px 0;
}

.footer h4 {
    font-weight: 400;
    font-size: 14px;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .navbar {
        padding: 0 15px;
        flex-wrap: wrap;
        height: auto;
    }

    .navbar a {
        width: auto;
        padding: 0 15px;
    }

    .question_list {
        margin: 30px auto;
        padding: 0 15px;
    }

    .question_list h1 {
        font-size: 28px;
        margin-bottom: 30px;
    }

    .question_list table {
        font-size: 14px;
    }

    .question_list table th,
    .question_list table td {
        padding: 12px 8px;
    }
}

@media (max-width: 480px) {
    .navbar a {
        font-size: 13px;
        padding: 0 10px;
        width: auto;
    }

    .question_list h1 {
        font-size: 24px;
    }

    .question_list table th,
    .question_list table td {
        padding: 10px 5px;
        font-size: 13px;
    }

    .question_list table .item {
        height: 45px;
    }
}